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Monitoring and modeling of diurnal and seasonal odour and gas emissions from different types of swine roomsWang, Yuanyuan 04 January 2008 (has links)
The issue of odour, greenhouse gas emissions and indoor air quality in swine buildings have become a great concern for the neighbouring communities as well as governments. Air dispersion models have been adopted widely as an approach to address these problems which determine science-based distance between livestock production site and neighbours. However, no existing model considers the diurnal and seasonal variations of odour, gas (ammonia, hydrogen sulphide, greenhouse gas), and dust concentrations and emissions, which may cause great uncertainty. The primary objective of this project is to monitor and model the diurnal and seasonal variations of odour, gases, and dust concentrations and emissions from nursery, farrowing, and gestation rooms. Additionally, this study tried to quantify the greenhouse gas contribution from swine buildings and evaluate the indoor air quality of swine barns. <p>Strip-block experimental design was used to measure the diurnal variation of odour and gas concentrations and emissions in PSC Elstow Research Farm. It was found that: 1) odour and gas concentrations in winter were significantly higher than those in mild and warm weather conditions for all three rooms (P<0.05); 2) the nursery room had higher level of odour and gas concentration and emission than the other two types of rooms, no significant difference existed between the farrowing and gestation rooms (P>0.05); 3) significant diurnal variations occurred in August and April (P<0.05) for odour and some gas concentrations and emissions, while no significant diurnally variations were found in February (P>0.05); 4) apparent diurnal variation patterns were observed in August and April for NH3, H2S and CO2 concentrations, being high in the early morning and low in the late afternoon; 5) positive correlation was found between odour concentrations and NH3, H2S, and CO2 concentrations, respectively. <p>A whole year ( August 2006 to July 2007) monitoring of odour, gas and dust concentrations and emissions revealed that: 1) significant seasonal effect on odour and gas concentrations and emissions, total dust concentrations and dust depositions were observed (P<0.05), but no specific variation pattern was discovered for odour and gas emissions; 2) the total greenhouse gas emission from all the rooms in the gestation, nursery and farrowing area was 2956 CO2 equivalent tons per year, where gestation area, nursery area, and farrowing area accounted for 39.3 %, 37.2% and 23.5%, respectively; the CO2 emission contributed 53.4% to the total greenhouse emission, and CH4 contributed to 43.9%, 2.7% for N2O; N2O could be considered negligible; 3) indoor air quality of the swine barn met the requirements set by the Occupational Health and Safety Regulations (1996) of Saskatchewan for NH3, H2S, and CO2. <p>Statistical models were developed for each type of room to predict the odour and gas concentrations and emissions based on four variables: ventilation rate, room temperature, ambient temperature, and animal unit. The predicted results showed agreeable with measured values for most models (R2 = 0.56-0.96). Generally, gas prediction models performed better (R2=0.61-0.96) than odour prediction models (R2=0.56-0.85).<p>This study was conducted in the province of Saskatchewan throughout one year and the results could be used as representative data for Canada Prairies. Due to the large diurnal and seasonal variabilities of odour emissions, it was recommended to take multiple measurements of odour emission rate under different weather conditions in order to improve the accuracy of air dispersion modeling.
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Luftqualität in Sachsen: JahresberichtPausch, Annette, Löschau, Gunter 17 December 2012 (has links) (PDF)
Der Bericht informiert über die Messergebnisse zur Luftbelastung im Freistaat Sachsen.
An 29 Messstellen werden kontinuierlich die Konzentrationen der Luftschadstoffe Schwefeldioxid, Stickstoffdioxid, Feinstaub-Partikel (PM10 und PM2,5), Blei, Benzol und Ozon überwacht.
In den Städten Leipzig, Dresden, Chemnitz, Zwickau und Görlitz wurde der 24-Stunden-Grenzwert der Partikelkonzentration (PM10) an verkehrsnahen Messstellen verletzt. Der NO2-Jahresgrenzwert wurde, wie bereits in den vergangenen Jahren, in Dresden, Leipzig und Chemnitz nicht eingehalten.
Die Ozonsituation verbesserte sich nur leicht. Zielwerte zum Schutz der menschlichen Gesundheit und der Pflanzen wurden nur noch in den Höhenlagen des Erzgebirgskamms überschritten.
Die Konzentrationen von Schwefeldioxid, Feinstaub PM2,5, Benzol und Blei lagen auf dem Niveau der Vorjahre und damit weit unter den gesetzlichen Grenzwerten.
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Predictive Modeling of Near Dry Machining: Mechanical Performance and Environmental ImpactLi, Kuan-Ming 22 June 2006 (has links)
The objective of this study is to develop a methodology to analyze the air quality and tool performance in turning process under near-dry condition. Near dry machining refers to the use of a very small amount of cutting fluid in the machining process. In order to implement the near dry machining technology, this dissertation develops the analytical models for both tool life and aerosol generation prediction. This research includes predictive models of cutting temperatures, cutting forces, tool wear progressions, and aerosol generation. The comparison of air quality and tool performance among dry machining process, near dry machining process, and flood cooling machining process is also presented. It is found that according to the selected cutting conditions in the model-based comparisons, the predicted cutting forces, cutting temperature and power consumption under near dry lubrication are reduced as high as about 30% compared with those in dry cutting but these predicted values are higher than those in wet cutting by about 10% under the same cutting conditions while the predicted tool wear land lengths are reduced by 60% compared with those in dry cutting but these values are higher than those in wet cutting about 1% under the same cutting conditions. However, the air quality for near dry machining with 12.5 ml/hr oil flow rate is worse than that for wet cutting due to different aerosol generation mechanisms.
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Evaluation of the TEOM method for the measurement of particulate matter for Texas cattle feedlotsSkloss, Stewart James 15 May 2009 (has links)
The Tapered Element Oscillating Microbalance (TEOM) sampler is an EPA
approved Federal Equivalent Method Sampler for measuring PM10 concentrations. The
Center for Agricultural Air Quality Engineering and Science (CAAQES) owns two
Rupprecht and Patashnick (R&P) Series1400a monitors. The R&P Series 1400a monitor
uses the TEOM method to measure particulate matter (PM) concentrations and was
approved by EPA in 1990 as an automated equivalent method PM10 sampler. Since its
approval, many state air pollution regulatory agencies (SAPRAs) have located R&P
Series 1400a monitors at community-oriented monitoring sites. Some SAPRAs have
even located TEOM samplers at the property line of major sources to determine if the
source is meeting its permit requirements for PMc emissions. This thesis presents the
results of PM10 and TSP concentrations measured with TEOM and low-volume
gravimetric samplers at two Texas cattle feedlots. The purpose of this research was to
compare the performance of the R&P Series 1400a monitor to the low-volume
gravimetric sampler when sampling PM from a feedlot. Furthermore, this research was conducted to avoid the inappropriate regulation of cattle feedlots that may occur in the
future as a consequence of the TEOM sampler being used to measure PMc emissions.
The results of this research demonstrate that relationship between the R&P Series
1400a monitor and the low-volume gravimetric sampler is linear. In general, it was
observed that the TEOM sampler measured higher PM10 and TSP concentrations than
the low-volume gravimetric sampler when sampling downwind from a cattle feedlot.
The opposite results were observed when sampling was conducted upwind from the
feedlot. The collected data demonstrates that the concentration difference between the
two sampling methods is linearly dependent with the concentration intensity for the
upwind sampling locations. This trend was shown to be statistically significant. Another
linear relationship was observed between the concentration difference and the particle
size (mass median diameter and geometric standard deviation) of the sampled dust.
Although this trend was not statistically significant, it is believed that additional
downwind concentration measurements would validate this relationship.
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Influence of traffic exhausts on the air quality in a street canyon¡GA case study of measurement results in Fung-Shan City, Kaohsiung CountyWen, Chi-Shemg 19 June 2004 (has links)
Spatial distributions of gaseous pollutants CO, NOx, and SO2 in a street canyon in Fung-Shan, Kaohsiung County were measured. The street runs west-to-east with two lanes in a single direction: traffic flows only from west to east. The street canyon is 60 m long (= L) and 20 m wide (= W). The heights of the five-story buildings on both sides of the street are about 16 m (= H). Therefore, the street canyon has an aspect ratio AR (= H/W) = 0.8, and a length to width ratio L/H = 3. Air was sampled on site on three consecutive days, 3 September to 5 September, in 2003. The sampling period were 20 h long, from 00:00 to 19:00 on September 4, but covered only the two rush hours, 07:00-10:00 and 16:30-20:00, on the other two days. Traffic emissions were also estimated using available emission factors from TANEEB (1992).
Results show that motorcycles are dominant vehicle in the street. Emission estimations indicate that motorcycle contributed to about 75% of CO emission, automobiles contributed about 80% of NOx emissions, while motorcycles and automobiles each contributed about 50% of SO2 emissions. Variations of traffic emissions generally follow traffic flow rates, indicating reasonable estimations of traffic emissions.
When wind blows perpendicularly to the street canyon, air pollutants tend to accumulate in the leeward side. For example, concentration of CO in the leeward side is about two times that in the windward side. Generally, concentrations of air pollutants decrease with height, about 10% to 20% reduction in concentration, particularly noticeable in the leeward side. Results also show that, on leeward side, concentrations of air pollutants in the corridor were lower than those outside the corridor, being about 53.3% difference in CO concentration. However, on windward side, concentrations of air pollutants in the corridor were higher than those outside the corridor, being about 100% difference in NO2 concentration.
Keywords: Street Canyon, Mobile Sources, Air Quality, Emission Factor.
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A Feasible Evaluation and Analysis of Visual Air Quality Index in Urban AreasChang, Kuo-chung 21 July 2006 (has links)
This research analyzed the weather information (temperature, wind velocity, visibility, and total cloudiness) from the Taipei and the Kaohsiung Weather Station of Central Weather Bureau, and air pollution from the Air Quality Monitoring Station of Environmental Protection Administration, Executive Yuan ( Shihlin, Shihlin, Jhongshan, Wanhua, Guting, Songshan¡A), Nanzih, Zuoying, Cianjin, and Siaogan ) to evaluate the feasibility of using visibility as the ambient air quality index by statistical analysis¡C
In regard to the visibility in Taipei metropolis, the visibility between 1983~1992 showed a steady status between 5~11 kilometers. The visibility after 1993 has increased gradually between 6~16 kilometers, which indicated that the visual air quality has been improved year by year in Taipei metropolis. In regard to the visibility in Kaohsiung metropolis, the index has a trend of decreasing year by year from 10~24 kilometers to 2~12 kilometers, and the decrease was particularly obvious after 1993.
Analyzing the air quality index greater than 100 in the metropolis, the visibility is categorized as the level of "poor", which means that the visibility is within 3 kilometers. When the air quality index ranges between 76~100, the visibility is categorized as the level of median, which means the visibility is within 4 kilometers. When the air quality index ranges between 50~75, the visibility is categorized as the level of "good", which means the visibility is within 7 kilometers. When the air quality index ranges between 20~49, the visibility is categorized as the level of "excellent", which means the visibility is beyond 7 kilometers.
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Source contributions of suspended particles using Air Quality Model and Receptor ModelWang, Wen-Cheng 21 December 2008 (has links)
Air quality of the Kao-Ping airshed has been the worst of all airsheds which are divided into seven groups by districts in Taiwan. The percentage of annual bad air quality (Pollution Standard Index, PSI > 100) in the Kao-Ping airshed (6.65−13.56%) was twice than it in the Yun-Chia-Nan airshed (2.58−6.98%) during the past decade (1998−2007). Oil refineries, petrol/plastic industries, power plants, and iron/steel/metal plants are the major industries in the Kaohsiung metropolitan area. Due to intensive industrial and traffic activities, the Kao-Ping area has the poorest air quality in Taiwan − either increased ground-level concentrations of particulate matter (PM) or ozone (O3) associated with unfavorable meteorological conditions − particularly between late fall and mid-spring
The temporal and spatial characterization of suspended particles in the Kao-Ping area was analyzed by using TAPM (air quality model) and CMB (receptor model) to understand the contributions of the major emission sources. Estimations using the TAPM model suggest that point-source emissions were the predominant contributors (about 49.1%) to PM10 concentrations at Hsiung-Kong industrial site in Kaohsiung City, followed by area sources (approximately 35.0%) and neighboring transport (7.8%). Because Ping-Tung City (urban) and Chao-Chou town (rural) are located downwind of Kaohsiung City when north or northeasterly winds prevail, the two sites also experience severe pollution events despite the lack of industrial sources; neighboring transport contributed roughly 39.1% to PM10 concentrations at Ping-Tung and 48.7% at Chao-Chou.
Results of CMB (chemical mass balance) modeling show that the main contributors to PM2.5 mass are vehicle exhaust (gasoline vehicle emission: 43% and diesel vehicle emission: 17% at Hsiung-Kong; gasoline vehicle emission: 45% and diesel vehicle emission: 19% at Ping-Tung; gasoline vehicle emission: 12% and diesel vehicle emission: 29% at Chao-Chou). And the main contribution to PM2.5-10 mass is the paved road emission (Hsiung-Kong: 40%; Ping-Tung: 48%; Chao-Chou: 50%). It is recommended that air quality model is an appropriate tool to large area and receptor model is more suitable to specific point to identify emission sources by the results in this study.
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Effects of Automoblie Tailpipe Emissions in the Hsuehshan Tunnel on the Air Quality of Neighboring Areas Using ADMS ModelWang, Chen-wen 30 June 2009 (has links)
The Hsuehshan tunnel, whose length is about 12.9 kilometers, is the longest tunnel in Taiwan and Southeast Asia. Since the tunnel is used, it reduces the traveling time from Taipei to Ilan and brings the convenience of transportation; but the vehicles and pollution sources are added. Furthermore, the concentrations of pollutants are increased by accumulation in the long tunnel.
This study estimates the effects of automobile tailpipe emissions in the Hsuehshan tunnel on the air quality of neighboring areas by using Atmospheric Dispersion Modelling System for Roads (ADMS-Roads). This work simulates carbon monoxide (CO), nitrous oxides (NOx) and sulfur dioxide (SO2) at two sites (Pin-Ling and Tou-Cheng management centers) in northern Taiwan in winter of 2008. The average concentrations of CO, NOx and SO2 at Pin-Ling (Tou-Cheng) management centers respectively are 0.49 (0.55) ppm, 10.60 (14.83) ppb and 4.80 (7.47) ppb on non-holiday and 0.66 (0.64) ppm, 16.88 (15.12) ppb and 4.70 (4.20) ppb on holiday. It shows that the concentrations of pollutants on holiday are higher than on non-holiday by increasing vehicles.
Simulated results show that effects of traffic exhaust in the tunnel on the air quality of neighboring areas are less. Estimations using the ADMS-Roads suggest that the emissions are not the predominant contributors at two sites. The effect is the highest with northern (northeastern) winds at the southern (northern) area of the Hsuehshan tunnel. Comparisons between simulations and measurements at both sites are satisfactory. Simulated values are generally in agreement with measured values, with a correlation coefficient of R = 0.37 ¡V 0.81, the index of agreement (IOA) = 0.58 ¡V 0.77, and the normalized mean square error (NMSE) = 0.03 ¡V 0.25. The ADMS-Roads will be applied to assess the environmental impact while the tunnel will be allowed more types of vehicles to drive in the future.
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Physicochemical Characteristic Analysis of Atmosphere Suspended Particles in the Heavy Industry Peripheral AreaChou, Yu-kuang 09 September 2009 (has links)
Kaohsiung city for the south Taiwan industry strategic place, the Siaogang area is a heavy industry stands in great numbers the area, the rendering plant, the steel plant, petrifies the factory, the incineration plant, the shipyard, the airport and so on, moreover also has transport means and so on the container truck, carriage vehicle, airplane, The air quality fraction defective occupies crown of the whole city. Kaohsiung important empty unclean control key of suspended particulate pollution, This research is for the purpose of discussing Physicochemical characteristic analysis of air suspended particles in the heavy industry peripheral area, understood in the heavy industry peripheral area air the suspended particles pollutant originates. Physicochemical characteristic analysis discussion atmosphere pollutants to influence Siaogang area. This research in May 2009 period picks each time continual sampling 24 hours to carry on each week twice sampling respectively, the East, West, South and North central area average in the Siaogang area 5 points, altogether gathers 20 samples. Another gathers motorcycle/automobile/diesel car/boiler/voltaic arc boiler/fritting furnace/road dusts different of samples, altogether 14 samples.
This research uses air sampling instrument (GAST) carries on the sampling to air of the Siaogang area. Using the scanning type electron microscope (Scanning electron microscope, SEM) and instruments and so on XRD (X-ray Diffractometer, XRD) carry on the metallic element and the physicochemical characteristic analysis. The time can of because of the Siaogang area atmosphere in the suspended particulate matter origin type and the contribution quantity, relevance of in order to help control of air suspended particles in the heavy industry peripheral area pollutant and the source of pollution.
This research the main of purpose this study by under construction in the air in the surrounding areas of heavy industry in the pollutants of sampling technology, and discussion of pollutants by the scene size distribution and inorganic salts, and so particulate surface characteristics and analysis for the structure and composition. This research also use a variety of discussion on the valuable instrument analysis to peripheral areas of heavy industry in the pollutants in air of surface and microstructure characteristics, the result of the above analysis, may further in-depth understanding of the heavy industries in peripheral areas of pollutants characteristics, also took granular than in the air pollutants and other kinds of granular pollutant emission sources and physicochemical characteristics of the apparent, discussion of heavy industry in peripheral areas of major sources of granular pollutants for source decrement measures.
Future expected completion of roads, schools, residential, farmland, rivers the downwind side of the land of bare ground, farming, construction site River dust, straw, dead wood, rubber, PVC plastic, PE/PP plastics non-heavy industry surrounding area of micro photo, composition and organizational analysis, and than the judgment against a database of all particulate sources.
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Measuring vehicle volumes and monitoring and modeling of PM2.5 concentrations in a travel center associated with a major urban interstate and interchangeYoon, Seung-Ju, January 2002 (has links) (PDF)
Thesis (M.S.)--University of Tennessee, Knoxville, 2002. / Title from title page screen (viewed [Sept. 27, 2002). Thesis advisor: Wayne T. Davis. Document formatted into pages (142 p. : ill (some col.)). Vita. Includes bibliographical references (p. 46-47).
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